Display apparatus comprising an electrode having a step difference
A display apparatus, including a circuit substrate including driver circuits and first bonding electrodes, and a pixel array on the circuit substrate and including a plurality of pixels each including first to third sub-pixels, and second bonding electrodes bonded to the first bonding electrodes, the pixel array further including, a plurality of first LED cells corresponding to the first and third sub-pixels, respectively, and each including a first conductivity-type semiconductor layer, a first active layer, and a second conductivity-type semiconductor layer, a plurality of second LED cells corresponding to the second sub-pixels, respectively, and each including the first conductivity-type semiconductor layer, a second active layer, and the second conductivity-type semiconductor layer, a first electrode extending to cover upper surfaces of the plurality of first and second LED cells and connected to the first conductivity-type semiconductor layers in common.
1 . A display apparatus, comprising:
a circuit substrate including driver circuits and first bonding electrodes; and
a pixel array on the circuit substrate and including a plurality of pixels each including first to third sub-pixels, and second bonding electrodes bonded to the first bonding electrodes, the pixel array further including:
a plurality of first LED cells corresponding to the first and third sub-pixels, respectively, and each including a first conductivity-type semiconductor layer, a first active layer, and a second conductivity-type semiconductor layer;
a plurality of second LED cells corresponding to the second sub-pixels, respectively, and each including the first conductivity-type semiconductor layer, a second active layer, and the second conductivity-type semiconductor layer;
a first electrode extending to cover upper surfaces of the plurality of first and second LED cells and connected to the first conductivity-type semiconductor layers in common;
a plurality of second electrodes on lower surfaces of the plurality of first and second LED cells, respectively, and connected to the second conductivity-type semiconductor layers, respectively; and
wavelength converters on the first LED cells in the third sub-pixels, wherein a lower surface of the first electrode is on a first level on the plurality of first LED cells and is on a second level lower than the first level on the plurality of second LED cells.
2 . The display apparatus as claimed in claim 1 , wherein the plurality of second electrodes are on the same level.
3 . The display apparatus as claimed in claim 1 , wherein an upper surface of the first electrode is on a third level on the plurality of first LED cells and is on a fourth level lower than the third level on the plurality of second LED cells.
4 . The display apparatus as claimed in claim 1 , wherein the first active layer and the second active layer include materials having different compositions.
5 . The display apparatus as claimed in claim 1 , wherein the pixel array further includes a transparent insulating layer on the plurality of first and second LED cells on a fifth level corresponding to a level of the wavelength converters in the first and second sub-pixels and not including a wavelength conversion material.
6 . The display apparatus as claimed in claim 1 , wherein the pixel array further includes a light blocking layer on the first electrode in regions including regions between the plurality of first and second LED cells.
7 . The display apparatus as claimed in claim 6 , wherein the plurality of first LED cells and the plurality of second LED cells have different widths.
8 . The display apparatus as claimed in claim 1 , wherein the pixel array further includes reflective layers surrounding side surfaces of the wavelength converters.
9 . The display apparatus as claimed in claim 1 , wherein the pixel array further includes:
color filters on the wavelength converters; and
microlenses on the plurality of first and second LED cells in the first and second sub-pixels and on the color filters in the third sub-pixels.
10 . The display apparatus as claimed in claim 1 , wherein:
the circuit substrate further includes a first bonding insulating layer surrounding the first bonding electrodes and forming an upper surface of the circuit substrate, and
the pixel array further includes a second bonding insulating layer surrounding the second bonding electrodes, forming a lower surface of the pixel array and being bonded to the first bonding insulating layer.
11 . The display apparatus as claimed in claim 1 , wherein the first to third sub-pixels are arranged in a diamond pentile structure.
12 . A display apparatus, comprising:
a circuit substrate including driver circuits; and
a pixel array on the circuit substrate and including a plurality of pixels, the pixel array further including:
a plurality of LED cells included in the plurality of pixels;
a first electrode covering upper surfaces of the plurality of LED cells, extending horizontally to a region between the plurality of LED cells, and connected to the plurality of LED cells in common; and
a plurality of second electrodes on lower surfaces of the plurality of LED cells, respectively, and connected to the plurality of LED cells, respectively,
wherein upper surfaces of a portion of the plurality of LED cells are on a first level, and upper surfaces of the other portion of the plurality of LED cells are on a second level lower than the first level.
13 . The display apparatus as claimed in claim 12 , wherein the first electrode is a single layer.
14 . The display apparatus as claimed in claim 12 , wherein:
each of the plurality of pixels includes first to third sub-pixels,
the plurality of LED cells include first LED cells corresponding to the first and third sub-pixels, respectively, and second LED cells corresponding to the second sub-pixels, respectively, and
each of the first LED cells includes a first active layer, and each of the second LED cells includes a second active layer.
15 . The display apparatus as claimed in claim 14 , wherein upper surfaces of the first LED cells are on the first level, and upper surfaces of the second LED cells are on the second level.
16 . The display apparatus as claimed in claim 12 , wherein:
each of the plurality of pixels includes first to third sub-pixels,
the plurality of LED cells include first LED cells corresponding to the first sub-pixels, respectively, second LED cells corresponding to the second sub-pixels, respectively, and third LED cells corresponding to the third sub-pixels, respectively, and
each of the first LED cells includes a first active layer, each of the second LED cells includes a second active layer, and each of the third LED cells includes a third active layer.
17 . The display apparatus as claimed in claim 16 , wherein upper surfaces of the first LED cells are on the first level, and upper surfaces of at least one of the second LED cells and the third LED cells are on the second level.
18 . The display apparatus as claimed in claim 12 , wherein the first electrode includes regions having different thicknesses.
19 . A display apparatus, comprising:
a circuit substrate including driver circuits; and
a pixel array on the circuit substrate and including a plurality of pixels each including first to third sub-pixels, the pixel array further including:
a plurality of LED cells corresponding to the first and third sub-pixels, respectively;
a first electrode extending to cover upper surfaces of the plurality of LED cells and connected to the plurality of LED cells in common; and
a plurality of second electrodes on lower surfaces of the plurality of LED cells, respectively, and connected to the plurality of LED cells, respectively,
wherein:
a lower surface of the first electrode is on a first level on a portion of the plurality of LED cells, and is on a second level lower than the first level on a portion of the plurality of LED cells, and
lower surfaces of the plurality of second electrodes are on the same level.
20 . The display apparatus as claimed in claim 19 , wherein the pixel array further includes wavelength converters on at least a portion of the plurality of LED cells in the first level.